Amplification of the c-met, c-erbB-2 and epidermal growth factor receptor gene in human gastric cancers: correlation to clinical features.

We examined amplification of the c-met, c-erbB-2, and epidermal growth factor receptor (EGFR) gene in the patients with primary gastric cancer, and compared the data with clinical features in order to clarify the relationship between oncogenic abnormality and clinical features. Oncogene amplifications were examined by slot blot hybridization using DNAs extracted from formalin-fixed and paraffin-embedded tissues of primary gastric cancers. Seven of the seventy cancers (10.0%) had c-met gene amplification, nine (12.9%) had c-erbB-2 gene amplification, and six (8.6%) had EGFR gene amplification, respectively. Eighteen cases (25.7%) exhibited one or multiple oncogene amplification, and two cases (2.9%) exhibited simultaneous amplification of the three genes. The cases with c-met gene amplification tend to show invasive character and were related to peritoneal dissemination. The cases with c-erbB-2 gene amplification were related to lymph node metastasis. The cases with EGFR gene amplification had large tumors and were in highly advanced stage. The survival rate in patients with oncogene amplification was significantly lower than that in patients without amplification. Our data indicated that these genes were related to growth and metastasis of gastric cancer. Furthermore, this study about the three genes suggested that the type of activated gene might decide on the type of metastasis and clinical features.